A Low-Power Adaptive Receiver Utilizing Discrete-Time Spectrum-Sensing

A flexible spectrum-sensing receiver in 65-nm CMOS consists of a wideband front-end spectrum-adaptive (SA) filtering, switched-capacitor amplifiers, and a filtering specific absorption rate ADC. The SA filter uses a discrete-time (DT) spectrum-analyzer and a reconfigurable DT notch filter to detect and suppress strong interferers over a 55-MHz range. In IEEE 802.15.4 tests, the receiver exceeds sensitivity and interferer rejection requirements. With SA filtering enabled, it achieves ≥ + 55-dB rejection from + 25- to + 65-MHz FM interferers.